Alchemical symbols, originally devised as part of alchemy, were used to denote some elements and some compounds until the 18th century. Note that while notation like this was mostly standardized, style and symbol varied between alchemists, so this page lists the most common.

Seven metals are associated with the seven classical planets, and seven deities, all figuring heavily in alchemical symbolism. Although the metals occasionally have a glyph of their own, the planet's symbol is used most often, and the symbolic and mythological septenary is consistent with Western astrology. The planetary symbolism is limited to the seven wandering stars visible to the naked eye, and the extra-Saturnarian planets such as Neptune are not used.

The alchemical magnum opus was sometimes expressed as a series of chemical operations. In cases where these numbered twelve, each could be assigned one of the Zodiac signs as a form of cryptography. The following example can be found in Pernety's 1758 Mytho-Hermetic Dictionary:[3]